# 2D complex function plot -- djm -- 08 sept 2006 # restart;with(plots):# define POLYNOMIAL here P := (x+I*y)^3 -2*(x+I*y)^2 -2*(x+I*y) - 3;# positive-valued contours plot1 := contourplot(Re(P),x=-5...5,y=-5...5,grid=[25,25],contours = [10,20,30,40,50,60,70,80],color=black):plot2 := contourplot(Im(P),x=-5...5,y=-5...5,grid=[25,25],contours = [10,20,30,40,50,60,70,80],color=blue):# zero contours plot3 := contourplot(Re(P),x=-5...5,y=-5...5,grid=[100,100],contours = [0],color=black,thickness=2):plot4 := contourplot(Im(P),x=-5...5,y=-5...5,grid=[100,100],contours = [0],color=blue,thickness=2):# negative-valued contours plot5 := contourplot(Re(P),x=-5...5,y=-5...5,grid=[25,25],contours = [-80,-70,-60,-50,-40,-30,-20,-10],color=black,linestyle=2):plot6 := contourplot(Im(P),x=-5...5,y=-5...5,grid=[25,25],contours = [-80,-70,-60,-50,-40,-30,-20,-10],color=blue,linestyle=2):# plot the roots zroots := [[-1/2,sqrt(3)/2],[-1/2,-sqrt(3)/2],[3,0]];plot7 := plot(zroots,color=red,style=POINT,symbol=CIRCLE,thickness=5,symbolsize=5):display({plot1,plot2,plot3,plot4,plot5,plot6,plot7});